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141.
Haiping Zhang Bailian Cai Anke Geng Huanyin Tang Wenjun Zhang Sheng Li Ying Jiang Rong Tan Xiaoping Wan Zhiyong Mao 《Aging cell》2020,19(2)
The decline in DNA repair capacity contributes to the age‐associated decrease in genome integrity in somatic cells of different species. However, due to the lack of clinical samples and appropriate tools for studying DNA repair, whether and how age‐associated changes in DNA repair result in a loss of genome integrity of human adult stem cells remains incompletely characterized. Here, we isolated 20 eyelid adipose‐derived stem cell (ADSC) lines from healthy individuals (young: 10 donors with ages ranging 17–25 years; old: 10 donors with ages ranging 50–59 years). Using these cell lines, we systematically compared the efficiency of base excision repair (BER) and two DNA double‐strand break (DSB) repair pathways—nonhomologous end joining (NHEJ) and homologous recombination (HR)—between the young and old groups. Surprisingly, we found that the efficiency of BER but not NHEJ or HR is impaired in aged human ADSCs, which is in contrast to previous findings that DSB repair declines with age in human fibroblasts. We also demonstrated that BER efficiency is negatively associated with tail moment, which reflects a loss of genome integrity in human ADSCs. Mechanistic studies indicated that at the protein level XRCC1, but not other BER factors, exhibited age‐associated decline. Overexpression of XRCC1 reversed the decline of BER efficiency and genome integrity, indicating that XRCC1 is a potential therapeutic target for stabilizing genomes in aged ADSCs. 相似文献
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143.
Jiaxin Zheng Shoulin Zhang Huijun Chen Xiaojun Cai Chunjian Zhang Shuhua Li Yabin Zhou Jing Shang Shunyu Liang Fengzhen Yao 《Cell biology international》2020,44(1):189-199
Protosappanin‐A (PrA) and oleanolic acid (OA), which are important effective ingredients isolated from Caesalpinia sappan L., exhibit therapeutic potential in multiple diseases. This study focused on exploring the mechanisms of PrA and OA function in podocyte injury. An in vitro model of podocyte injury was induced by the sC5b‐9 complex and assays such as cell viability, apoptosis, immunofluorescence, quantitative real‐time polymerase chain reaction, and western blot were performed to further investigate the effects and mechanisms of PrA and OA in podocyte injury. The models of podocyte injury were verified to be successful as seen through significantly decreased levels of nephrin, podocin, and CD2AP and increased level of desmin. The sC5b‐9‐induced podocyte apoptosis was inhibited in injured podocytes treated with PrA and OA, accompanied by increased protein levels of nephrin, podocin, CD2AP, and Bcl2 and decreased levels of desmin and Bax. The p‐AKT/p‐mTOR levels were also reduced by treatment of PrA and OA while AKT/mTOR was unaltered. Further, the effects of PrA and OA on injured podocytes were similar to that of LY294002 (a PI3K‐AKT inhibitor). PrA and OA were also seen to inhibit podocyte apoptosis and p‐AKT/p‐mTOR levels induced by IGF‐1 (a PI3K‐AKT activator). Our data demonstrate that PrA and OA can protect podocytes from injury or apoptosis, which may occur through inhibition of the abnormal activation of AKT‐mTOR signaling. 相似文献
144.
Chen S. L. Zhang L. P. Cai X. M. Bian L. Luo Z. X. Li Z. Q. Ge L. G. Chen Z. M. Xin Z. J. 《Russian Journal of Plant Physiology》2020,67(3):572-580
Russian Journal of Plant Physiology - The tea geometrid Ectropis grisescens is an important pest of tea plant (Camellia sinensis (L.) O. Kuntze). It feeds on the new leaves and tender... 相似文献
145.
Guoguo Ye Yujuan Wang Xiaoyun Liu Qiannan Dong Quanxin Cai Zhiming Yuan Han Xia 《PLoS neglected tropical diseases》2020,14(11)
Advances in technology have greatly stimulated the understanding of insect-specific viruses (ISVs). Unfortunately, most of these findings are based on sequencing technology, and laboratory data are scarce on the transmission dynamics of ISVs in nature and the potential effects of these viruses on arboviruses. Mesonivirus is a class of ISVs with a wide geographical distribution. Recently, our laboratory reported the isolation of a novel strain of mesonivirus, Yichang virus (YCV), from Culex mosquitoes, China. In this study, the experimental infection of YCV by the oral route for adult and larvae mosquitoes, and the vertical transmission has been conducted, which suggests that YCV could adopt a mixed-mode transmission. Controlled experiments showed that the infectivity of YCV depends on the mosquito species, virus dose, and infection route. The proliferation curve and tissue distribution of YCV in Cx. quinquefasciatus and Ae. albopictus showed that YCV is more susceptible to Ae. albopictus and is located in the midgut. Furthermore, we also assessed the interference of YCV with flaviviruses both in vitro and in vivo. YCV significantly inhibited the proliferation of DENV-2 and ZIKV, in cell culture, and reduced transmission rate of DENV-2 in Ae. albopictus. Our work provides insights into the transmission of ISVs in different mosquito species during ontogeny and their potential ability to interact with mosquito-borne viruses. 相似文献
146.
Chun-Yu Liu Min Wang Hong-Min Yu Fang-Xuan Han Qiong-Shi Wu Xing-Jun Cai 《Bioscience, biotechnology, and biochemistry》2020,84(8):1621-1628
ABSTRACT A critical pathogenic factor in the development of lethal liver failure is cell death induced by the accumulation of lipid reactive oxygen species. In this study, we discovered and illuminated a new mechanism that led to alcoholic liver disease via ferroptosis, an iron-dependent regulated cell death. Study in vitro showed that both necroptosis inhibitor and ferroptosis inhibitors performed significantly protective effect on alcohol-induced cell death, while apoptosis inhibitor and autophagy inhibitor had no such effect. Our data also indicated that alcohol caused the accumulation of lipid peroxides and the mRNA expression of prostaglandin-endoperoxide synthase 2, reduced the protein expression of the specific light-chain subunit of the cystine/glutamate antiporter and glutathione peroxidase 4. Importantly, ferrostatin-1 significantly ameliorated liver injury that was induced by overdosed alcohol both in vitro and in vivo. These findings highlight that targeting ferroptosis serves as a hepatoprotective strategy for alcoholic liver disease treatment. 相似文献
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149.
Tietao Wang Yihang Qi Zhihan Wang Jingru Zhao Linxuan Ji Jun Li Zhao Cai Liang Yang Min Wu Haihua Liang 《Molecular microbiology》2020,114(5):857-869
The GntR family regulators are widely distributed in bacteria and play critical roles in metabolic processes and bacterial pathogenicity. In this study, we describe a GntR family protein encoded by PA4132 that we named MpaR (M vfR-mediated P QS and a nthranilate r egulator) for its regulation of Pseudomonas quinolone signal (PQS) production and anthranilate metabolism in Pseudomonas aeruginosa. The deletion of mpaR increased biofilm formation and reduced pyocyanin production. RNA sequencing analysis revealed that the mRNA levels of antABC encoding enzymes for the synthesis of catechol from anthranilate, a precursor of the PQS, were most affected by mpaR deletion. Data showed that MpaR directly activates the expression of mvfR, a master regulator of pqs system, and subsequently promotes PQS production. Accordingly, deletion of mpaR activates the expression of antABC genes, and thus, increases catechol production. We also demonstrated that MpaR represses the rhl quorum-sensing (QS) system, which has been shown to control antABC activity. These results suggested that MpaR function is integrated into the QS regulatory network. Moreover, mutation of mpaR promotes bacterial survival in a mouse model of acute pneumonia infection. Collectively, this study identified a novel regulator of pqs system, which coordinately controls anthranilate metabolism and bacterial virulence in P. aeruginosa. 相似文献